Mining machine



1940- L. E. MITCHELL MINING MACHINE Original File d' March 21, 1934 S Sheets-Sheet l mmm O N ONN Dwm OZ //W/Y70R: LEWIS EM ITCHELL,

NOV. 12, 1940. n-c 2,221,454

MINING MACHINE Original Filed March 21, 1954 5 Sheets-Sheet 2 fiWE/YTOR: LEWIS E. MITCH ELL,

ag 3 5w M A/ NA r Nov. 12, 1940.

L. E. MITCHELL MINING MACHINE Original Filed March 21, 1934 3 Sheets-Sheet 3 LEwls E. MITCHELL,

Patented Nov. 12, 1940 UNITED STATES PATENT OFFICE MINING MACHINE ration of Ohio Original application March 21, 1934, Serial No.

716,660. Divided and this application November 21, 1936, Serial No. 112,127

4 Claims.

My invention relates to low vein, longwall, bottom Keri-cutting machines comprising a pivoted cutter bar adapting it to be used for either shortwall operations, or longwall operations, and one of the objects of my invention is the provision of improved and simplified construction in a device of this type.

A further object of the invention is the provision of a one way jaw clutch with operating means which when operated will retain the clutch in condition to effect a connection whenever the. drive shaft is operated in the correct direction but which will permit operation of said drive shaft in the reverse direction without transmission of power.

Further objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings,

Fig. 1 represents a plan View of the mining machine embodying my improvement;

Fig. 2 is a side elevational view of the mining machine shown in Fig. 1;

Fig. 3 is an enlarged plan view with certain parts removed and others shown in section, of the haulage or front end of the machine shown at the right hand end of Fig. 1;

Fig. 4 is a sectional elevation taken on the line 4-4 of Fig. 3 looking in the direction of the arrows; I

Fig. 5 is an elevational view of the interior structure shown in section at the right hand portion of Fig. 4, the section being taken on the line 5-5 of Fig. 3 looking in the direction of the arrows;

Fig. 6 is a sectional elevation taken on the section line 6-6 of Fig. 3, lookingin the direction of the arrows, Fig. 6 being in elevation similar to Fig. 5 but omittingcertain parts and adding others; and

Fig. 7 is a sectional plan View taken on the .line 7-1 of Fig. 6;

This application is a division of my application for an improvement in Mining machines, Serial No. 716,660, filed March 21, 1934.

By referring to Figs. land 2, it will be seen that the supporting framework of the mining machine comprises an intermediate motor section locking mechanism comprising vertical pins 41,

41 is relied on to hold the kerf cutter in the position shown in Fig. 1 during the shortwall operations, or to hold the kerf cutter in laterally projecting positions for longwall operations. The elongated kerfcutter 46 comprises elongated cutter bar 48 with a chain cutter 49'arranged to travel on the periphery thereof. I

The feeding and haulage section 44 comprises flexible draft elements which may be ropes as shown at 50.and 5| ,in Fig. 1, the free ends of which are adapted to be connected to fixed anchorages extraneous to the machine.

As shown in Fig. 1 a cover plate 65 is provided for section 45 and may be secured by means of bolts 69 to the vertical wall plates of the boxlike enclosure thereof. I

Referring now to the haulage and feeding section 44 of the machine, it will be seen that the forward end of the armature shaft of an electric motor in motor section 43 is .coupled to a shaft I4I journaled in ball bearings and secured to the worm I42 which meshes with a worm wheel I43 journaled on the vertical shaft M4. By means of threebolts I45 an eccentric cam I46 is rigidly secured to the hub portion I41 of the worm gear I43. The Worm gear I43 and the eccentric cam I46 are respectively mounted on spaced ball bearings I48 and I49 for free rotation relatively to the vertical shaft I44. When the motor operates to rotate the worm I42 rotary motion is imparted through the worm gear 143 to the eccentric cam I46 to freely rotate the latter on the ballbearings I48, I49 relatively to the vertical shaft I44.

When theeccentric cam I46 rotates it engages a circular ring I56 which is mounted by means of the roller bearings I5I for free rotation on the vertical bearing I52, as shown in Figs. 3 and 4.

The ring roller I56 and the vertical bearing I52 are carried on thebell crank lever I53 as shown in Fig. 3. This bell crank lever is pivoted at I54 where it is supported by the frame I55 for oscillation on a fixed vertical axis.

To that end of the bell crank lever I53 remote from its pivot I54, is pivoted at I56 a screw rod I51 which is adjustably connected to the screwthreaded block I58, thelatter being pivoted at I59 to the oscillating pawl carrier I6 By referring to Fig. 4, it will be seen that the pawl carrier I66 is provided with a central circular portion which is journaled on the hub- I6I of the ratchet wheel I52, the latter being keyed. as indicatedat I63 to the upper end portion of the vertical shaft I44. The pawl carrier I60 may be locked in place as shown in Fig. 4 by means of the cylindrical bracket I64 suspended from the bottom of the plate I65 which isv secured by bolts I61 to the box-like structure comprising the vertical plates I58.

I The cover plate I65 may be fastened to the plate I65 by the machine screws I56, there being aperturesin the plate 166 that may fit over the heads of bolts I61 as shown in Fig. 1.

A central circular cover plate I69 may be connected by means of the screws I15 as shown in Fig. 1, to the central portion of the plate I65. When the plate IE9 is removed access may be had to the chamber I1I to lubricate the ball bearings I12 which fit in the cylindrical recess in the bracket I54. The ball bearings I12 afford a means of journaling the upper end of the vertical shaft I44 in the bracket I64.

When the cover plate I65 is removed access may be had to the chamber I13 and the mecha-- nism therein. It should be understood that the chamber I13, when all the parts are assembled and when the covers are attached, affords a closed lubricating chamber for the worm gearing and the ratchet feeding mechanism, all of the parts shown in Fig. 4' in the chamber I13 running in oil.

Pivoted at I14 to the pawl carrier I60 is a spring pressed pawl I15 in position to engage the teeth of the ratchet wheel H52. It will thus be seen that when the cam IE5 is rotated, the bell crank lever I53 will be oscillated and the pawl and ratchet mechanism will be intermittently actuated to effect a step by step feeding movement of the vertical shaft I44 in an anti-clockwise direction as viewed in Fig. 3. A spring pressed retaining pawl I16 is pivotally mounted on the axis [I5 1 for movement independently of the bell crank lever I53 and in position to engage the ratchet teeth to prevent reverse movement of the vertical'shaft I44. By means of the adjustment which may be effected between the members 151 and I53 the pawl I15 may be adjusted so as to properly enter the notch between the ratchet teeth when the roller I55 is nearest the vertical shaft IM.

The rotation of the cam M5 thrusts the roller I outwardly away from the shaft I44 and thereby causes a forward anti-clockwise movement of the pawl I15 together with the ratchet wheel I62.

, In order to return the pawl I15 to its initial position a restoring spring shown at I11 in Fig. 3 is relied upon. This spring is located in the tube between the transverse partition I19 and the head I80 which is pivotally connected at lBI to the link I82 the other end of which is pivoted at I83 to the bell crank lever I53.

The restoring movement or return throw of the pawl I15 may be varied or regulated in accordance with the extent of feed desired by mechanism including hand wheel I for adjust ing the tube having partition I19 in the tubular casing I86. I

Adjustments may also be made to cause the pawl I15 to move the ratchet wheel either one notch, two notchese, three notches, or four notches, as may be desired. Full speed feeding transmission mechanism may thus be effected for purposes hereinafter more fully explained. It should be particularly noted, howeventhat all feeding movements or'step by step advances of the ratchet wheel IBZare unidirectional irrespective of the direction of rotation of the armature shaft. That is'to say, it is immaterial whether the motor is rotating in one direction or in a reverso direction. The rotation of 'the cam I46 will a ways cause oscillationof thebell-crank I53 so that the reciprocation of the pawl I15 will always be the same and the rotation of the shaft I44 as viewed in Fig. 3 will always be in an anticlockwise direction.

At the lower end of the vertical shaft IM as shown in Fig. 4 is a pinion I91 which meshes with a gear I98 journaled by means of the ball bearings I99 to the vertical bearing 2% extending upwardly from the bottom plate 20! of the supporting frame of the haulage and feeding section 45. The gear I98 meshes with the relatively larger gear 2&2 which is keyed at 2133 to the cylindrical hub 204 to the upper end of which is connected one element 255 of a friction clutch 205, the other element 201 of which is located on the interior of the rope drum 2118. The bushing 209 is pressed into the sleeve 2M for journaling on the vertical stationary bearing 2H1, the latter being secured to the top plate 23 by being keyed thereto as shown in Fig. 4.

The gear 202 meshes with a similar gear mounted to rotate about vertical bearing 2I2 which is similar to the vertical bearing 2 It. Also mounted to rotate about the vertical axis of the bearing M2 is a rope drum 213, and between the similar gear and the rope drum ZIS is a sleeve friction clutch and rope drum similar in all respects to the structure shown at the left hand portion of Fig. 4. The gear 292 rotates in an anti-clockwise direction as viewed in plan and the similar gear rotates in a clockwise direction and the ratio between these gears is such that the gear 2H will rotate approximately ten percent faster than the similar gear.

As shown in Fig. 4 the hub 2 I5 is provided with a cup-shaped bearing 2I4 which is held against rotation relative to the bottom plate 255 by means of the pin 2I5. The hub 216 of the large spur gear 252 rests on the bearing plate 2 i i within the cylindrical flange 2I1 which affords an oil cup. This hub 2I6 carries the portion 254 of the clutch element 265. The upper end of the hub 2I5 is provided with a ring packing 2I8 which bears against the inner surface of the stationary ring 2 I 9 to form a dirt seal, the ring 219 being mounted in a circular opening in the cover plate 226. This cover plate may be provided with an extension for the space in which the similar gear rotates. A vertical extension may also be provided at 222- (Fig. 4)

By providing a floor 221 for the chamber I13 as shown in Fig. 4, a separate closed chamber 228 maybe provided for the spur gearing. The central portion of the floor plate 221 may also afford support for the outer race of the ball bearing 230. Suitable lubricating means may be provided for the spur gearing in the closed chamber Connected to and woundon the rope drum 2.98 is a rope 55 the free end of which is adapted to be connected to a fixed anchorage in the mine extraneous to the machine. Connected to. and wound on the rope drum 2 I3 is a rope 51 the free end of which is also adapted to be connected to a fixed anchorage in the mine. The application of'power transmitted from the motor to each rope drum is controlled by the friction clutch associated therewith. As'above stated, each of the rope drums 288 and 2M} is provided with its own friction clutch and each friction clutch is operated by the'mechanism shown in Fig. l.

A transverse top plate 234 is securely bolted to the side walls of the frameof the section M and the upper ends of the vertical cylindrical bearings -2I0 an'd -2I2 are -secure'd thereto as to a ainst.

prevent rotation of said vertical bearings relative to the supporting frame of the machine.

Beneath the plate 234 and keyed to the stationary bearing 2III at 235 is a screw-threaded bushing 236 which is provided in its lower inner side With a seat 231 for a ball bearing 238. It will thus be seen that the sleeve 204 is mounted so that it will have no vertical movement relative to the bearing 2| 0 but may rotate with the bush ing 209 while provided with the thrust bearing 238 at its upper end.

Journaled on the bushing 239 surrounding the sleeve 204 is a sleeve-shaped hub 240 at the interior of the rope drum 208. The rope drum is therefore mounted for rotation on the sleeve 204 and the latter in turn is mounted for rotation about the vertical axis of the bearing 2 I0.

Mounted at the upper side of the drum 208 as shown at 24I is the outer race 242 of a ball bearing 243 the inner race 244 of which is riveted as shown at 245 to the wheel 246 screwthreaded on to the screw-threaded bushing 236.

Radial spokes or handles 241 on the wheel 246, some of which handles always project out from beyond the plate234, may be used to turn the wheel 246 on the screw 236 to lift or lower the ball bearing 243. This ball bearing supports the rope drum and also the clutch member 201. Therefore, when the ball bearing 243 is lifted the clutch is applied to direct transmission of power from the spur gear 202 to the flexible draft element or rope 50. In a similar manner transmission of power from the similar spur gear to the rope drum 2 I3 connected thereto may be effected by grasping the radial handles 241' and turning the wheel 246' to obtaina pull on the rope 5I. As shown in Fig. 3, when the two rope drums are rotated in opposite directions and each unithe upper sheave 233 being used when the rope 59 I is directed around the same. One directional sheave 248 is sufficient for the rope drum connected to the larger spur gear 202.

At the rear end of the machine a directional sheave 249 may be mounted on an arm 250 which is detachably connected at 250 to a depending bracket at either corner on opposite sides of the machine. During longwall operations the brackets remain within the confines of the supporting framework.

In order to slide the machine over the mine bottom at a relatively fast or haulagespeed, mechanism is provided as shown in Figs. 4 to 7 inclusive, for connecting the worm wheel I43 directly to the shaft I44 and the pinion I 91 to drive the latterindependently of the pawl and ratchet feeding mechanism shown in Fig. 3. By means of the handle 253 connected to the rock shaft 254 which is journaled on the bearing 255, the slotted disc 56 may be moved clockwise from the position shown in Fig. 6 to a clutch applying position and held there after the handle 253 is released.

to the pinion I91.

ter being mounted in a tube 262 the lower end of which is connected to the L-shaped member 263 secured to the arm 264. The other end of the arm 264, as shown in Fig. '1, is secured to a tube 255 journaled on a bearing rod 266 mounted in the brackets 261 and 268. Secured to the other end of the tube 265 is another arm 269. Trunnions 210, 210 carrying a ring 21I, are journaled in bearings at the outer ends of the arms 264 and 259 as shown in Fig. '1.

Carried by the ring 21I is a lower clutch element 212 which is provided with beveled clutch.

teeth 212' adapted to engage the upper clutch element 213 secured to the lower side of the worm gear I43 and having teeth 213 as shown in Figs. 4 and 6. The lower clutch element 212 is discshaped and its periphery fits in an inner annular groove of the ring 21I. The latter may be constructed of semicircular parts bolted together as shown at 214, 214 in Fig. 7 to clamp the ring ring 21I to the clutch elements 212.

It should be particularly noted that the interior meshing teeth 212 and 213 are provided with such beveled surfaces that when the worm gear I43 is rotated in a clockwise direction as viewed in plan, the clutch 212, 213, will be ineffective to transmit power from the motor to the pinion I91. While it is immaterial whether the motor rotates in one direction or the other when I clockwise direction when power is applied directly,

Therefore, when the clutch 212, 213 is applied the motor must be rotated in the proper direction to secure anti-clockwise rotation of the ratchet wheel I 62 and the shaft I44.

Any attempt to do otherwise would cause the pawl? I15 to lock the shaft I44 against rotation whereupon the clutch teeth 212 and 213 will slip relatively to each other even though the pivot pin 258 is held at dead center or beyond, by the spring 26 I.

In other words, when the clutch is applied by means of the handle 253 it will be spring-loaded and the beveling of the clutch teeth will necessitate rotation of the motor in the proper direction to maintain run-directional rotation of the driving spur gears for the two rope drums. Consequently, whether the rope drums are rotated by means of the slow speed pawl and ratchet mechanism or by means of the fast speed haulage mechanism the rope drums can be rotated by power only in such directions as to wind up the ropes thereon and can never be operated by power to pay out the ropes. When the ropes are tobe payed out the friction clutches may be released to free the drums and the ropes can then be pulled manually for the anchoring of the free ends thereof at predetermined locations in a mine.

As shown in Figs. 2 and 3 all of the feeding and haulage mechanism is located between the top and bottom planes of the machine and between the spaced apart vertical planes which eX- tend through the sides of the cutter frame. The pawl and ratchet feeding mechanism shown in Fig. 3 comprises only a single vertical shaft I44 and the manual mechanism for operating the high speed or haulage clutch shown in Figs. 6 and is permanently located inside of the adjacent vertical plane extending through the side of the machine.

As shown in Fig. 4 the worm gear I43 is detachably connected to the cam I46. A plurality of openings spaced circumferentially on the worm gear M3 may be provided so that the cam Mt may have a plurality of positions with respect to the worm gear M3. This arrangement enables the life of the worm gear 563 to be prolonged by adjustment thereof to a new position after wear or a maximum load. The pawl H5 is driving the ratchet wheel 62 in an anti-clockwise direction as viewed in'Fig. 3. In other words, the eccentric cam 5% is adjustably secured to the worm wheel M3 so that the relative positions of these parts may be varied to allow a plurality of separate places on the worm wheel in turn to be placed in the position of maximum load and wear, thus securing the greatestpossible wear from the worm wheel before replacement is necessary.

It should also be noted that only six gears in all and a ratchet wheel are required to drive the two drums and attain numerous feeding speeds and a relatively fast haulage speed when the clutch of Figs. 6 and 7 is thrown in. In order to enable the use of rope drums each relatively large in diameter while maintaining reduction in the "width of the machine, these rope drums are mounted with their vertical axes in a diagonal vertical plane as shown in Fig. 3. That is to say, the space ahead of the motor is utilized for the location of the rope drums and the feeding and hauling mechanism connected thereto, and the rope drums are diagonally arranged within the lateral confines of the machine so that their diameters may be increased. The direction sheaves 233 andfiit also have their vertical axes within the side limits of the machine so that their peripheries will be in positions to direct the ropes approximately in alinement with the sides of the machine when arranged as shown in Fig. 3.

The directional sheaves 2 33 and 233 shown in Figs. 1 and 2 for receiving the ropes 50, 5E direct from the rope drums are preferably tapered upwardly or provided with a conical surface to facilitate the winding of the ropes on the drums and the unwinding of the same therefrom during the various operations above described. Such tapering tends to keep the ropes up notwithstanding fioor anchorages, thereby assuring proper winding of the ropes onto the rope drums.

The term Shortwall used herein is the trademark of The Jeffrey Manufacturing Company, a corporation of Ohio, the assignee of this application, said trade-mark having been registered October 31, 1911, in Class 23, Cutlery, machinery, and tools, and parts thereof, registration No. 84,006, and renewed June 9, 1931.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended and we therefore wish not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what I desire to secure by Letters Patent of the United States is:

1. In apparatus of the class described, a gear train including a shaft and means for driving it comprising a clutch having a direct drive element, of a driven element, another drive element for driving said shaft including means preventing rotation of said driven element in one direction, said direct drive and driven elements having cooperating sets of teeth at least one set of which is beveled, and operating means for said clutch including means to shift said direct drive and driven elements into engaging relation, said operating means including a spring which allows said direct drive element to rotate while said driven element remains stationary when said operating means is in clutch engaging position, should said direct drive element be driven in the wrong direction.

2. In apparatus of the class described, the combination with a shaft, of a gear train for driving said shaft including a slow speed'pawl and ratchet drive, a retaining pawl preventing reverse rotation of said shaft, a high speed drive including a jaw clutch having cooperating teeth one group of which is beveled, and operating means for said jaw clutch so constructed and arranged that when said gear train is driven to rotate said shaft against the action of said retaining pawl the clutch elements will slip relative to each other.

3. In apparatus of the class described, the com bination with a shaft to be driven, of means for driving said shaft in one direction and preventing movement thereof in the opposite direction, a clutch for driving said shaft independently of said driving means, said clutch comprising toothed drive and driven elements at least one of which has beveled teeth whereby when said drive element rotates in the proper direction said shaft will be driven and when it rotates in the opposite direction said clutch will become disengaged, and

means for releasably holding said teeth in engagement.

4. In apparatus of the class described, the combination with an element to be driven, of means for driving said element in one direction at one speed including pawl and ratchet mechanism having a retaining pawl to prevent reverse rotation of said element, a clutch for driving said element independently of said pawl and ratchet mechanism, said clutch comprising drive and driven elements so constructed and arranged as to drive said element to be driven positively in one direction and to slip when said'drive element is rotated in a reverse direction, and means for releasably holding said drive and driven elements in operative relation regardless of the direction said drive element is driven.

LEWIS E. MITCHELL. 

